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1.	Grigorenko, L, et al. (author) Scientific program of DERICA-prospective accelerator and storage ring facility for radioactive ion beam research 2019 In: Physics-Uspekhi. - 1468-4780 .- 1063-7869. ; 62:7, s. 675-690 Journal article (peer-reviewed)abstract Studies of radioactive ions (RIs) are the most thriving field of low-energy nuclear physics. In this paper, the concept and the scientific agenda of the prospective accelerator and storage ring facility for RI beam (RIB) research are proposed for a large-scale international project based at the Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research. The motivation for the new facility is discussed and its characteristics are briefly presented and shown to be comparable to those of advanced world centers, the so-called "RIB factories". In the project, the emphasis is made on studies with short-lived RIBs in storage rings. A unique feature of the project is the possibility of studying electron-RI interactions in a collider experiment to determine the fundamental properties of nuclear matter, in particular, electromagnetic form factors of exotic nuclei.
2.	Axelsson, L., et al. (author) Study of the unbound nucleus 11N by elastic resonance scattering 1996 In: Physical Review C (Nuclear Physics). - 0556-2813 .- 2469-9985 .- 2469-9993. ; 54:4, s. 1511-1514 Journal article (peer-reviewed)abstract Resonances in the unbound nucleus 11N have been studied, using the resonance scattering reaction 10C+p. The data give evidence for three states above the 10C+p threshold with energies 1.30, 2.04, and 3.72 MeV. These states can be interpreted, in a potential-model analysis, as the ground state and the first two excited states with spin-parity 1 / 2+, 1 / 2-, and 5 / 2+ arising from the shell-model orbitals 1s1 / 2, 0p1 / 2, and 0d5 / 2. A narrow state superposed on a broad structure found at higher energy could be interpreted as the mirror state of the 3 / 2- in 11Be shifted down in energy. This shift would suggest a large radius of the potential.
3.	Fomichev, A. S., et al. (author) Recent results related to excited states of 6Be and 10He 2012 In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 38, s. Art. no. 15002- Conference paper (peer-reviewed)abstract The 1H(6Li,6Be)n charge-exchange reaction and the 3H(8He, p)10He two-neutron transfer reaction were recently carried out at the ACCULINNA fragment separator (FLNR, Dubna) to populate the ground and excited states of 6Be and 10He nuclei, respectively. The 6Be ET spectrum (ET is the 6Be energy above its 4He+p+p decay threshold) was obtained with high statistics and described by the well-known 0+ ground state of 6Be at ET = 1.37 MeV, the 2+ state at ET = 3.05 MeV and a broad structure extending from 4 to 16 MeV which could be interpreted as the isovector soft dipole mode associated with the 6Li ground state. In the 10He case the 0+ ground state was found at about 2.1(2) MeV (T ∼ 2 MeV) above the 8He+n+n breakup threshold. Angular correlations observed for 10He decay products show prominent interference patterns allowing to draw conclusions about the structure of low-energy excited states: 1- (E T ∼ 5 MeV) and 2+ (ET > 6 MeV).
4.	Bergmann, U.C., et al. (author) On the b-decay of 9C 2001 In: Nuclear Physics A. ; 692:3-4, s. 427-450 Journal article (peer-reviewed)abstract In β-decay experiments on 9C at CERN/ISOLDE the β-strength was determined to the ground state, the 12.2 MeV excited state and the Isobaric Analog State (IAS) at 14.655 MeV in 9B. A large β-strength asymmetry is deduced for the mirror transitions of 9C and 9Li to states around 12 MeV excitation energy. A satisfactory description of the three-body decay from a narrow energy region around the 12.2 MeV resonance is obtained within a sequential model involving the ground and first-excited states of 5Li and 8Be. From the study of angular correlations the spin of the 12.2 MeV state is determined as 5/2−. For the first time the population of the IAS is observed in β-decay and new information on the decay of this state is obtained. The advantages of a closely packed, highly segmented detector setup are demonstrated.
5.	Bezbakh, A.A., et al. (author) Evidence for the First Excited State of H 7 2020 In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 124:2 Journal article (peer-reviewed)abstract The H7 system was populated in the H2(He8,He3)H7 reaction with a 26 AMeV He8 beam. The H7 missing mass energy spectrum, the H3 energy and angular distributions in the H7 decay frame were reconstructed. The H7 missing mass spectrum shows a peak, which can be interpreted either as unresolved 5/2+ and 3/2+ doublet or one of these states at 6.5(5) MeV. The data also provide indications of the 1/2+ ground state of H7 located at 1.8(5) MeV with quite a low population cross section of ∼25 μb/sr within angular range θc.m.≃(17°-27°).
6.	Chudoba, V., et al. (author) Detailed Study of External Correlations in the Low-Energy Spectrum of Beryllium-6 2019 In: Bulletin of the Russian Academy of Sciences: Physics. - 1062-8738 .- 1934-9432. ; 83:4, s. 392-398 Journal article (peer-reviewed)abstract Three-body continuum p-p-α for the charge exchange reaction 1H(6Li,6Be)n is studied in detail. The data are obtained with a high volume of statistics (approximately 4.7 million events), making it possible to analyze three-particle correlations. Detailed information about the structure of 6Ве and the reaction is obtained as a result.
7.	Chudoba, V., et al. (author) Three-body correlations in direct reactions: Example of Be 6 populated in the (p,n) reaction 2018 In: Physical Review C. - 2469-9993 .- 2469-9985. ; 98:5 Journal article (peer-reviewed)abstract The Be6 continuum states were populated in the charge-exchange reaction H1(Li6,Be6)n collecting very high statistics data (∼5×106 events) on the three-body α+p+p correlations. The Be6 excitation energy region below ∼3MeV is considered, where the data are dominated by contributions from the 0+ and 2+ states. It is demonstrated how the high-statistics few-body correlation data can be used to extract detailed information on the reaction mechanism. Such a derivation is based on the fact that highly spin-aligned states are typically populated in the direct reactions.
8.	Fomichev, A. S., et al. (author) Isovector soft dipole mode in Be-6 2012 In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 708:1-2, s. 6-13 Journal article (peer-reviewed)abstract By using the H-1(Li-6,Be-6)n charge-exchange reaction, population of continuum states in Be-6 was observed up to E-T = 16 MeV, E-T being the Be-6 energy above its three-body decay threshold. In kinematically complete measurements performed by detecting alpha + p + p coincidences, an E-T spectrum of high statistics was obtained, containing approximately similar to 5 x 10(6) events. The spectrum provides detailed correlation information about the well-known 0(+) ground state of Be-6 at E-T = 1.37 MeV and its 2(+) state at E-T = 3.05 MeV. Moreover, a broad structure extending from 4 to 16 MeV was observed. It contains negative parity states populated by Delta L = 1 angular momentum transfer without other significant contributions. This structure can be interpreted as a novel phenomenon, i.e. the isovector soft dipole mode associated with the Li-6 ground state. The population of this mode in the charge-exchange reaction is a dominant phenomenon for this reaction, being responsible for about 60% of the cross-section obtained in the measured energy range.
9.	Fomichev, A. S., et al. (author) Lifetime of 26S and a Limit for its 2p Decay Energy 2011 In: International Journal of Modern Physics E. - : World Scientific Pub Co Pte Lt. - 0218-3013 .- 1793-6608. ; 20:6, s. 1491-1508 Journal article (peer-reviewed)abstract The unknown isotope (26)S, expected to decay by two-proton (2p) emission, was studied theoretically and searched experimentally. The structure of this nucleus was examined within the relativistic mean field (RMF) approach. A method for taking into account the many-body structure in the three-body decay calculations was developed. The results of the RMF calculations were used as an input for the three-cluster decay model optimized for the study of a possible 2p decay branch of this nucleus. The experimental search for (26)S was performed by fragmentation of a 50.3 A MeV (32)S beam. No events of a particles table (26)S or (25)P (a presumably proton-unstable subsystem of (26)S) were observed. Based on the obtained production systematics, an upper half-life limit of T(1/2) 640 keV for (26)S. Analogous limits for (25)P are found as T(1/2) 110 keV. In the case that the one-proton emission is the main branch of the (26)S decay, a limit Q(2p) > 230 keV would follow for this nucleus. According to these limits, it is likely that (26)S resides in the picosecond life time range
10.	Fynbo, H. O. U., et al. (author) The beta 2p decay mechanism of Ar-31 2000 In: Nuclear Physics A. - 0375-9474. ; 677, s. 38-60 Journal article (peer-reviewed)abstract We have measured the beta-decay of Ar-31 with a high granularity setup sensitive to multiparticle decay branches. Two-proton emission is observed from the isobaric analog state in Cl-31 to the four lowest states in P-29 and furthermore from a large number of states fed in Gamow-Teller transitions. The mechanism of two-proton emission is studied via energy and angular correlations between the two protons. In all cases the mechanism is found to be sequential yielding information about states in S-30 up to 8 MeV excitation energy. Improved data on the beta-delayed one-proton branches together with the two-proton data provide precise information about the beta-strength distribution up to 15 MeV excitation energy.
11.	Grieser, M., et al. (author) Storage ring at HIE-ISOLDE 2012 In: European Physical Journal: Special Topics. - : Springer Science and Business Media LLC. - 1951-6401 .- 1951-6355. ; 207:1, s. 1-117 Journal article (peer-reviewed)abstract We propose to install a storage ring at an ISOL-type radioactive beam facility for the first time. Specifically, we intend to setup the heavy-ion, low-energy ring TSR at the HIE-ISOLDE facility in CERN, Geneva. Such a facility will provide a capability for experiments with stored secondary beams that is unique in the world. The envisaged physics programme is rich and varied, spanning from investigations of nuclear ground-state properties and reaction studies of astrophysical relevance, to investigations with highly-charged ions and pure isomeric beams. The TSR might also be employed for removal of isobaric contaminants from stored ion beams and for systematic studies within the neutrino beam programme. In addition to experiments performed using beams recirculating within the ring, cooled beams can also be extracted and exploited by external spectrometers for high-precision measurements. The existing TSR, which is presently in operation at the Max-Planck Institute for Nuclear Physics in Heidelberg, is well-suited and can be employed for this purpose. The physics cases as well as technical details of the existing ring facility and of the beam and infrastructure requirements at HIE-ISOLDE are discussed in the present technical design report.
12.	Grieser, M., et al. (author) Storage ring at HIE-ISOLDE Technical design report 2012 In: The European Physical Journal Special Topics. - : Springer Science and Business Media LLC. - 1951-6355 .- 1951-6401. ; 207:1, s. 1-117 Research review (peer-reviewed)abstract We propose to install a storage ring at an ISOL-type radioactive beam facility for the first time. Specifically, we intend to setup the heavy-ion, low-energy ring TSR at the HIE-ISOLDE facility in CERN, Geneva. Such a facility will provide a capability for experiments with stored secondary beams that is unique in the world. The envisaged physics programme is rich and varied, spanning from investigations of nuclear ground-state properties and reaction studies of astrophysical relevance, to investigations with highly-charged ions and pure isomeric beams. The TSR might also be employed for removal of isobaric contaminants from stored ion beams and for systematic studies within the neutrino beam programme. In addition to experiments performed using beams recirculating within the ring, cooled beams can also be extracted and exploited by external spectrometers for high-precision measurements. The existing TSR, which is presently in operation at the Max-Planck Institute for Nuclear Physics in Heidelberg, is well-suited and can be employed for this purpose. The physics cases as well as technical details of the existing ring facility and of the beam and infrastructure requirements at HIE-ISOLDE are discussed in the present technical design report.
13.	Grigorenko,, et al. (author) Deep excursion beyond the proton dripline. II. Toward the limits of existence of nuclear structure 2018 In: Physical Review C. - 2469-9985 .- 2469-9993. ; 98:6 Journal article (peer-reviewed)abstract Prospects of experimental studies of argon and chlorine isotopes located far beyond the proton dripline are studied by using systematics and cluster models. The deviations from the widespread systematics observed in Cl-28,Cl-29 and Ar-29,Ar-30 have been theoretically substantiated, and analogous deviations have been predicted for the lighter chlorine and argon isotopes. The limits of nuclear structure existence are predicted for Ar and Cl isotopic chains, with Ar-26 and Cl-25 found to be the lightest sufficiently long-living nuclear systems. By simultaneous measurements of protons and gamma rays following decays of such systems as well as their beta-delayed emission, an interesting synergy effect may be achieved, which is demonstrated by the example of Cl-30 and Ar-31 ground-state studies. Such a synergy effect may be provided by the new EXPERT setup (EXotic Particle Emission and Radioactivity by Tracking) being operated inside the fragment separator and spectrometer facility at GSI, Darmstadt.
14.	Kostyleva, D., et al. (author) Towards the Limits of Existence of Nuclear Structure: Observation and First Spectroscopy of the Isotope K-31 by Measuring Its Three-Proton Decay 2019 In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 123:9 Journal article (peer-reviewed)abstract The most remote isotope from the proton dripline (by 4 atomic mass units) has been observed: K-31. It is unbound with respect to three-proton (3p) emission, and its decays have been detected in flight by measuring the trajectories of all decay products using microstrip detectors. The 3p emission processes have been studied by the means of angular correlations of S-28 + 3p and the respective decay vertices. The energies of the previously unknown ground and excited states of K-31 have been determined. This provides its 3p separation energy value S-3p of -4.6(2) MeV. Upper half-life limits of 10 ps of the observed K-31 states have been derived from distributions of the measured decay vertices.
15.	Markenroth, Karin, 1973, et al. (author) Crossing the dripline to N-11 using elastic resonance scattering 2000 In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 6203:3 Journal article (peer-reviewed)abstract The level structure of the unbound nucleus N-11 has been studied by C-10+p elastic resonance scattering in inverse geometry with the LISE3 spectrometer at GANIL, using a C-10 beam with an energy of 9.0 MeV/ nucleon. An additional measurement was done at the A1200 spectrometer at MSU. The excitation function above the C-10+p threshold has been determined up to 5 MeV. A potential-model analysis revealed three resonance states at energies 1.27(-0.05)(+0.18) MeV (Gamma = 1.44 +/- 0.2 MeV), 2.01(-0.05)(+0.15) MeV (Gamma = 0.84 +/- 0.2 MeV), and 3.75 +/- 0.05 MeV (Gamma = 0.60 +/- 0.05 MeV) with the spin-parity assignments I-pi=1/2+,1/2,-,5/2+, respectively. Hence, N-11 is shown to have a ground state parity inversion completely analogous to its mirror partner Be-11. A narrow resonance in the excitation function at 4.33 +/- 0.05 MeV was also observed and assigned spin parity 3/2-.
16.	Mukha, I. G., et al. (author) Deep excursion beyond the proton dripline. I. Argon and chlorine isotope chains 2018 In: Physical Review C. - 2469-9993 .- 2469-9985. ; 98:6 Journal article (peer-reviewed)abstract The proton-unbound argon and chlorine isotopes have been studied by measuring trajectories of their decay-in-flight products by using a tracking technique with microstrip detectors. The proton (1p) and two-proton (2p) emission processes have been detected in the measured angular correlations "heavy-fragment"+p and "heavy-fragment"+p+p, respectively. The ground states of the previously unknown isotopes Cl30 and Cl28 have been observed for the first time, providing the 1p-separation energies Sp of -0.48(2) and -1.60(8), MeV, respectively. The relevant systematics of 1p- and 2p-separation energies have been studied theoretically in the core+p and core+p+p cluster models. The first-time observed excited states of Ar31 allow one to infer the 2p-separation energy S2p of 6(34) keV for its ground state. The first-time observed state in Ar29 with S2p=-5.50(18) MeV can be identified as either a ground state or an excited state according to different systematics.
17.	Mukha, I., et al. (author) Observation and Spectroscopy of New Proton-Unbound Isotopes Ar-30 and Cl-29: An Interplay of Prompt Two-Proton and Sequential Decay 2015 In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 115:20, s. 7- Journal article (peer-reviewed)abstract Previously unknown isotopes Ar-30 and Cl-29 have been identified by measurement of the trajectories of their in-flight decay products S-28 + p + p and S-28 + p, respectively. The analysis of angular correlations of the fragments provided information on decay energies and the structure of the parent states. The ground states of Ar-30 and Cl-29 were found at 2.25(-0.10)(+0.15) and 1.8 +/- 0.1 MeV above the two-and one-proton thresholds, respectively. The lowest states in Ar-30 and Cl-29 point to a violation of isobaric symmetry in the structure of these unbound nuclei. The two-proton decay has been identified in a transition region between simultaneous two-proton and sequential proton emissions from the Ar-30 ground state, which is characterized by an interplay of three-body and two-body decay mechanisms. The first hint of a fine structure of the two-proton decay of Ar-30*(2(+)) has been obtained by detecting two decay branches into the ground and first-excited states of the S-28 fragment.
18.	Muzalevskii, I. A., et al. (author) Resonant states in H 7: Experimental studies of the H 2 (He 8, He 3) reaction 2021 In: Physical Review C. - 2469-9985 .- 2469-9993. ; 103:4 Journal article (peer-reviewed)abstract The extremely neutron-rich system H7 was studied in the direct H2(He8,He3)H7 transfer reaction with a 26 AMeV secondary He8 beam [Bezbakh et al., Phys. Rev. Lett. 124, 022502 (2020)PRLTAO0031-900710.1103/PhysRevLett.124.022502]. The missing mass spectrum and center-of-mass angular distributions of H7, as well as the momentum distribution of the H3 fragment in the H7 frame, were constructed. In addition, we carried out another experiment with the same beam but a modified setup, which was cross-checked by the study of the H2(Be10,He3)Li9 reaction. A solid experimental evidence is provided that two resonant states of H7 are located in its spectrum at 2.2(5) and 5.5(3)MeV relative to the H3+4n decay threshold. Also, there are indications that the resonant states at 7.5(3) and 11.0(3)MeV are present in the measured H7 spectrum. Based on the energy and angular distributions, obtained for the studied H2(He8,He3)H7 reaction, the weakly populated 2.2(5)-MeV peak is ascribed to the H7 ground state. It is highly plausible that the firmly ascertained 5.5(3)-MeV state is the 5/2+ member of the H7 excitation 5/2+-3/2+ doublet, built on the 2+ configuration of valence neutrons. The supposed 7.5-MeV state can be another member of this doublet, which could not be resolved in Bezbakh et al. [Phys. Rev. Lett. 124, 022502 (2020)PRLTAO0031-900710.1103/PhysRevLett.124.022502]. Consequently, the two doublet members appeared in the spectrum of H7 in the work mentioned above as a single broad 6.5-MeV peak.
19.	Nikolskii, E.Y., et al. (author) H 6 states studied in the H 2 (He 8, He 4) reaction and evidence of an extremely correlated character of the H 5 ground state 2022 In: Physical Review C. - 2469-9993 .- 2469-9985. ; 105:6 Journal article (peer-reviewed)abstract The extremely neutron-rich system H6 was studied in the direct H2(He8,He4)H6 transfer reaction with a 26A MeV secondary He8 beam. The measured missing mass spectrum shows a broad bump at ≈4-8 MeV above the H3+3n decay threshold. This bump can be interpreted as a broad resonant state in H6 at 6.8(5) MeV. The population cross section of such a presumably p-wave state (or it may be few overlapping states) in the energy range from 4 to 8 MeV is dσ/dωc.m.≃190-80+40μb/sr in the angular range 5°<θc.m.<16°. The obtained missing mass spectrum is practically free of H6 events below 3.5 MeV (dσ/dωc.m. 5μb/sr in the same angular range). The steep rise of the H6 missing mass spectrum at ≈3 MeV allows us to derive the lower limit for the possible resonant-state energy in H6 to be 4.5(3) MeV. According to the paring energy estimates, such a 4.5(3) MeV resonance is a realistic candidate for the H6 ground state (g.s.). The obtained results confirm that the decay mechanism of the H7 g.s. (located at 2.2 MeV above the H3+4n threshold) is the "true"(or simultaneous) 4n emission. The resonance energy profiles and the momentum distributions of fragments of the sequential H6→H5(g.s.)+n→H3+3n decay were analyzed by the theoretically updated direct four-body-decay and sequential-emission mechanisms. The measured momentum distributions of the H3 fragments in the H6 rest frame indicate very strong "dineutron-type"correlations in the H5 ground state decay.
20.	Nikolskii, E.Y., et al. (author) Study of proton and deuteron pickup reactions (d, 3 He), (d, 4 He) with 8 He and 10 Be radioactive beams at ACCULINNA-2 fragment separator 2023 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 541, s. 121-125 Journal article (peer-reviewed)abstract The extremely neutron-rich systems 7H, 6H were studied in the 2H(8He, 3He)7H and 2H(8He, 4He)6H proton and deuteron pickup reactions with a 26 AMeV secondary 8He beam produced at the new ACCULINNA-2 fragment separator. In addition, the same proton and deuteron pickup reactions were generated using the 42 AMeV 10Be beam, and the population of low-lying 9Li and 8Li states was measured in reactions 2H(10Be,3He)9Li and 2H(10Be,4He)8Li, respectively. The latter were used as reference measurements in order to check the setup calibration over the excitation energy of 7,6H and to determine the real experimental energy resolution which was compared with Monte Carlo calculations. The corresponding results obtained for the superheavy hydrogen systems 7H, 6H are presented and discussed. Typical excitation spectra of the 9Li and 8Li nuclei are also shown.
21.	Polettini, M., et al. (author) Decay studies in the A∼225 Po-Fr region from the DESPEC campaign at GSI in 2021 2022 In: Il Nuovo Cimento. - : Società Italiana di Fisica. - 2037-4909. ; 45:5 Journal article (peer-reviewed)abstract The HISPEC-DESPEC collaboration aims at investigating the structure of exotic nuclei formed in fragmentation reactions with decay spectroscopy measurements, as part of the FAIR Phase-0 campaign at GSI. This paper reports on first results of an experiment performed in spring 2021, with a focus on beta-decaystudies in the Po-Fr nuclei in the 220 < A <230 island of octupole deformation exploiting the DESPEC setup. Ion-beta correlations and fast-timing techniques are being employed, giving an insight into this difficult-to-reach region.
22.	Tanaka, Y. K., et al. (author) Search for eta '-mesic nuclei using (p,d) reaction with FRS/Super-FRS at GSI/FAIR 2020 In: Journal of Physics, Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 1643 Journal article (peer-reviewed)abstract We plan a semi-exclusive measurement of the C-12(p,dp) reaction to search for eta'-mesic nuclei, aiming at investigating in-medium properties of the eta'-meson. We employ a 2.5 GeV proton beam impinging on a carbon target to produce eta'-mesic C-11 nuclei via the C-12(p,d)eta'circle times C-11 reaction. Using coincidence measurements of the forward going deuterons, important for missing-mass spectroscopy, and decay protons emitted from the eta'-mesic nuclei for event selection will provide a high experimental sensitivity to observe eta'-mesic nuclei. We will perform the measurements by combining the WASA detector system with the fragment separator FRS at GSI and also with the Super-FRS at FAIR in the future. The plan of the experiments and the present status are reported.
23.	Axelsson, L., et al. (author) Beta decay of Ar-31 1998 In: Nuclear Physics A. - 0375-9474. ; 634:4, s. 475-496 Journal article (peer-reviewed)abstract A complete study of Ar-31 beta decay has been made by high-resolution charged-particle and gamma-ray spectroscopy. Beta-delayed radiation was detected by an array of three charged-particle detectors and a large-volume germanium detector. Fifteen new energy levels were discovered in Cl-31. The beta-strength distribution, measured to 14.5 MeV, is compared with a shell-model calculation in the full sd space. The quenching of the Gamow-Teller strength and the isospin impurity of the IAS in Cl-31 are discussed. (C) 1998 Published by Elsevier Science B.V.
24.	Axelsson, L., et al. (author) Two-proton emission in the decay of Ar-31 1998 In: Nuclear Physics A. - 0375-9474. ; 628:3, s. 345-362 Journal article (peer-reviewed)abstract Several beta-delayed two-proton branches were observed in the decay of Ar-31, the most intense ones proceeding through the isobaric analogue state (IAS) in Cl-31. The mechanism of the two-proton emission is studied via the energy and angular distributions of the two protons, Simultaneous emission of the two protons fits the present data well, sequential decays might also describe them. Independent of the decay mechanism, a spin of 5/2 for the IAS is suggested, An improved limit on the direct two-proton emission fi om the ground state of Ar-31 is presented, (C) 1998 Elsevier Science B.V.
25.	Bergmann, U. C., et al. (author) On the beta-decay of C-9 2001 In: Nuclear Physics A. - 0375-9474. ; 692:3-4, s. 427-450 Journal article (peer-reviewed)abstract In beta -decay experiments on C-9 at CERN/ISOLDE the beta -strength was determined to the ground state, the 12.2 MeV excited state and the Isobaric Analog State (IAS) at 14.655 MeV in B-9. A large beta -strength asymmetry is deduced for the mirror transitions of C-9 and Li-9 to states around 12 MeV excitation energy. A satisfactory description of the three-body decay from a narrow energy region around the 12.2 MeV resonance is obtained within a sequential model involving the ground and first-excited states of Li-5 and Be-8. From the study of angular correlations the spin of the 12.2 MeV state is determined as 5/2(-). For the first time the population of the IAS is observed in beta -decay and new information on the decay of this state is obtained. The advantages of a closely packed. highly segmented detector setup are demonstrated. (C) 2001 Elsevier Science B.V. All rights reserved.
26.	Borge, M. J. G., et al. (author) Proton dripline studies at ISOLDE: Ar-31 and C-9 2002 In: Nuclear Physics A. - 0375-9474. ; 701, s. 373C-377C Conference paper (peer-reviewed)abstract In this contribution examples of the application of new technologies to disentangle the mechanism of beta-delayed multiparticle emission are given. In particular the mechanism of beta-delayed two-proton emission from Ar-31 has been resolved and proved to be sequential, a preview of C-9-decay data is discussed. (C) 2002 Elsevier Science B.V. All rights reserved.
27.	Cubero, M., et al. (author) Do Halo Nuclei Follow Rutherford Elastic Scattering at Energies Below the Barrier? The Case of 11Li 2012 In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 109:26 Journal article (peer-reviewed)abstract The first measurement of the elastic scattering of the halo nucleus 11Li and its core 9Li on 208Pb at energies near the Coulomb barrier is presented. The 11Li+208Pb elastic scattering shows a strong reduction with respect to the Rutherford cross section, even at energies well below the barrier and down to very small scattering angles. This drastic change of the elastic differential cross section observed in 11Li+208Pb is the consequence of the halo structure of 11Li, as it is not observed in the elastic scattering of its core 9Li at the same energies. Four-body continuum-discretized coupled-channels calculations, based on a three-body model of the 11Li projectile, are found to explain the measured angular distributions and confirm that the observed reduction is mainly due to the strong Coulomb coupling to the dipole states in the low-lying continuum of 11Li. These calculations suggest the presence of a low-lying dipole resonance in 11Li close to the breakup threshold.
28.	Cubero, M., et al. (author) Elastic scattering of 9Li on 208Pb at energies around the Coulomb barrier 2011 In: AIP Conference Proceedings. - : AIP. - 1551-7616 .- 0094-243X. - 9780735409378 ; 1377, s. 338-340 Conference paper (peer-reviewed)abstract We have studied the dynamical effects of the halo structure of 11Li on the scattering on heavy targets at energies around the Coulomb barrier. This experiment was performed at ISAC‐II at TRIUMF with a world record in production of the post‐accelerated 11Li beam. As part of this study we report here on the first measurement of the elastic cross section of the core nucleus, i.e. 9Li on 208Pb, at energies around the Coulomb barrier. A preliminary optical model analysis has been performed in order to extract a global optical potential to describe the measured angular distributions.
29.	Cubero, M., et al. (author) Scattering of 9Li on 208Pb at energies around the Coulomb barrier 2011 In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. - 9782759806935 ; 17, s. Art. no. 16002- Conference paper (peer-reviewed)abstract In order to study the dynamics of 11Li and 9Li beams in a strong electric field at energies around the Coulomb barrier, we measured at the ISACII-TRIUMF Facility the angular distribution of elastic and inelastic scattering of 11Li+208Pb at 24.2 and 29.7 MeV and 9Li+208Pb at 24, 29.5 and 33 MeV laboratory energies. We present here the first determination of the angular distribution of the cross section of 9Li+208Pb. The results are compared with theoretical calculations using the double-folding São Paulo Potential (SPP) for the real part and a for the imaginary part a Woods-Saxon potential. A good overall agreement is obtained.
30.	De Witte, H., et al. (author) Nuclear Charge Radii of Neutron-Deficient Lead Isotopes Beyond N = 104 2007 In: Physical Review Letters. ; 98:11, s. 112502- Journal article (peer-reviewed)
31.	Fernandez-Garcia, J. P., et al. (author) 11Li Breakup on 208Pb at Energies Around the Coulomb Barrier 2013 In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 110:14 Journal article (peer-reviewed)abstract The inclusive breakup for the Li-11 + Pb-208 reaction at energies around the Coulomb barrier has been measured for the first time. A sizable yield of Li-9 following the Li-11 dissociation has been observed, even at energies well below the Coulomb barrier. Using the first-order semiclassical perturbation theory of Coulomb excitation it is shown that the breakup probability data measured at small angles can be used to extract effective breakup energy as well as the slope of B(E1) distribution close to the threshold. Four-body continuum-discretized coupled-channels calculations, including both nuclear and Coulomb couplings between the target and projectile to all orders, reproduce the measured inclusive breakup cross sections and support the presence of a dipole resonance in the Li-11 continuum at low excitation energy.
32.	Fernandez-Garcia, J. P., et al. (author) Li-11 structural information from inclusive break-up measurements 2015 In: EPJ Web of Conferences. - : EDP Sciences. - 2101-6275 .- 2100-014X. ; 88 Conference paper (peer-reviewed)abstract Structure information of Li-11 halo nucleus has been obtained from the inclusive break-up measurements of the Li-11+Pb-208 reactions at energies around the Coulomb barrier (E-lab = 24.3 and 29.8 MeV). The effective break-up energy and the slope of B(E1) distribution close to the threshold have been extracted from the experimental data.
33.	Fernandez-Garcia, J. P., et al. (author) Simultaneous analysis of the elastic scattering and breakup channel for the reaction Li-11+Pb-208 at energies near the Coulomb barrier 2015 In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 92:4 Journal article (peer-reviewed)abstract We present a detailed analysis of the elastic scattering and breakup channel for the reaction of Li-11 on Pb-208 at incident laboratory energies of 24.3 and 29.8 MeV, measured at the radioactive ion beam facility of TRIUMF, in Vancouver, Canada. A large yield of Li-9 fragments was detected by four charged particle telescopes in a wide angular range. The experimental angular and energy distributions of these Li-9 fragments have been compared to coupled-reaction-channel and continuum-discretized coupled-channel calculations. The large production of Li-9 fragments at small angles can be explained by considering a direct breakup mechanism, while at medium-large angles a competition between direct breakup and neutron transfer to the continuum of the Pb-208 target was observed.
34.	Fernandez-Garcia, J. P., et al. (author) Study of the break-up channel in 11Li+208Pb collisions at energies around the Coulomb barrier 2014 In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 515:1 Conference paper (peer-reviewed)abstract We present a study of 11Li+208Pb collisions at energies around the Coulomb barrier (Elab 24.3 and 29.8 MeV), measured at the post-accelerated beam facility, ISAC II, at TRIUMF (Vancouver, Canada). A remarkably large yield of 9Li has been observed, a result that is attributed to the weak binding of the 11Li nucleus. The angular distribution of this 9Li yield, relative to the elastic one, has been analysed in terms of first-order semiclassical calculations as well as four-body and three-body Continuum-Discretized Coupled-Channels (CDCC) calculations, based on a three-body and di-neutron model of the 11Li nucleus, respectively. The calculations reproduce well the trend of the data and support the existence of a large concentration of B(E1) strength at very low excitation energies. The connection of this large B(E1) with a possible low-lying dipole resonance is discussed. © Published under licence by IOP Publishing Ltd.
35.	Fomichev, A. S., et al. (author) Long range plan with radioactive beams at Dubna 2010 In: 3rd International Conference on Current Problems in Nuclear Physics and Atomic Energy, NPAE 2010; Kyiv; Ukraine; 7 June 2010 through 12 June 2010. ; , s. 64-69 Conference paper (peer-reviewed)abstract A program for upgrade of existing radioactive ion beams facilities at Flerov Laboratory of Nuclear Reactions, JINR Dubna is presented. A project of a new in-flight fragment separator ACCULINNA-2 is proposed. It is expected the new instrument will be more universal and powerful than the existing nowadays. The beam intensity should be increased by factor 10-15, its optical quality greatly improved and the range of the accessible secondary radioactive beams broadened up to Z∼20. Main ion-optical characteristics, operating principles and a tentative plan for the project realization are included. An extensive research program based on local experiments made so far and international proposals for these equipments is discussed.
36.	Fomichev, A. S., et al. (author) Status of the ACCULINNA-2 project at FLNR 2012 In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 337:1, s. Art. no. 012025- Conference paper (peer-reviewed)abstract The project of a new and more powerful in-flight fragment separator ACCULINNA-2 at U-400M cyclotron in FLNR, JINR planned to build in addition to the existing separator ACCULINNA is presented. The new separator will provide high intensity RIBs in the lowest energy range (5÷50 MeV/nucleon) which is attainable for in-flight separators. The possibilities for the astrophysics studies at the proposed device are presented. ACCULINNA-2 separator is planned to be constructed in the years 2010-2015. The current status of the project is reported.
37.	Fomichev, A. S., et al. (author) The Suggested New Fragment Separator ACCULINNA-2 2010 In: Acta Physica Polonica, Series B.. - 1509-5770 .- 0587-4254. ; 41:2, s. 475-480 Journal article (peer-reviewed)abstract We present new project of fragment separator ACCULINNA-2 that is being planned to be constructed in Flerov Laboratory of Nuclear Reaction, JINR. The ACCULINNA-2 facility is not, intended to compete with the, new large in-flight RIB facilities. It, should complement the existing/constructed facilities in certain fields. Namely, ACCULINNA-2 should provide high intensity RIBs in the lowest energy range attainable for in-flight separators.
38.	Fynbo, H. O. U., et al. (author) Ar-31 examined: New limit on the beta-delayed three-proton branch 1999 In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 59:4, s. 2275-2277 Journal article (peer-reviewed)abstract We have remeasured the decay of Ar-31 with a setup sensitive to multiparticle decay branches and obtained. a new limit of 1.1 x 10(-3) (99% C.L.) on the beta-delayed three-proton branch between the isobaric analog state in Cl-31 and the ground state of Si-28. This a factor of 17 below the previously reported first observation of beta-delayed three-proton emission in Ar-31. The limit on a possible beta 3p branch to the first excited state in Si-28 is 2.9 x 10(-4). [S0556-2813(99)04404-0].
39.	Honkanen, A., et al. (author) Fine structure in the beta-delayed proton decay of Ar-33 1996 In: Nuclear Physics A. - 0375-9474. ; 611:1, s. 47-55 Journal article (peer-reviewed)abstract Low-energy beta-delayed protons from Ar-33 have been measured for the first time, The data reveal states, which, despite unfavourable barrier penetrability values, strongly decay to the first excited 2(+) state in S-32. The observation is discussed in terms of the standard shell model, A natural explanation is provided by the large spectroscopic amplitudes, involving s(1/2) and d(3/2) orbitals, as well as the l = 0 barrier penetrability, favouring the decay to the 2(+) state.
40.	Krupko, S. A., et al. (author) Fragment separator ACCULINNA-2 2010 In: AIP Conference Proceedings. - : AIP. - 1551-7616 .- 0094-243X. - 9780735407688 ; 1224, s. 516-521 Conference paper (other academic/artistic)
41.	Yaneva, A., et al. (author) FAST-TIMING MEASUREMENT IN 96Pd: IMPROVED ACCURACY FOR THE LIFETIME OF THE 4+1 STATE 2023 In: Acta Physica Polonica B, Proceedings Supplement. - : Jagiellonian University. - 1899-2358 .- 2082-7865. ; , s. 1-1 Conference paper (peer-reviewed)abstract Direct lifetime measurements via γ–γ coincidences using the FATIMA fast-timing LaBr3(Ce) array were performed for the excited states below previously reported isomers. In the N = 50 semi-magic 96Pd nucleus, lifetimes below the Iπ = 8+ seniority isomer were addressed as a benchmark for further analysis. The results for the Iπ = 2+ and 4+ states confirm the published values. Increased accuracy for the lifetime value was achieved for the 4+ state.
42.	Aleksandrov, D., et al. (author) Halo excitations in fragmentation of He-6 at 240 MeV/u on carbon and lead targets 2000 In: Nuclear Physics A. - 0375-9474. ; 669:1-2, s. 51-64 Journal article (peer-reviewed)abstract Dissociation of a 240 MeV/u beam of He-6, incident on carbon and lead targets, has been studied in kinematically complete experiments to investigate low-lying excitation modes in the halo nucleus He-6. It is shown that alignment effects characterize the inelastic scattering and allow an unambiguous assignment of the spin of a narrow resonance observed in the excitation energy spectrum. The differential cross sections for the He-6 inelastic scattering on carbon and lead targets were deduced from the measured moments of the two neutrons and the a-particle. An analysis of these distributions shows that quadrupole and, possibly, monopole excitations characterize the hadronic interaction, while the dipole mode is dominating in Coulomb dissociation. Neither theoretically predicted new resonance states in He-6 nor nuclear excitation of a dipole mode were found. Direct evidence has been obtained for strong suppression of Coulornb post-acceleration in direct Coulomb breakup in a lead target.
43.	Aleksandrov, D., et al. (author) Invariant mass spectrum and alpha-n correlation function studied in the fragmentation of He-6 on a carbon target 1998 In: Nuclear Physics A. - 0375-9474. ; 633:2, s. 234-246 Journal article (peer-reviewed)abstract Momentum distributions and invariant mass spectra from the breakup of He-6 ions with an energy of 240 MeV/u interacting with a carbon target have been studied. The data were used to extract information about the reaction mechanism which is influenced by the structure of He-6. It is found that the dominant reaction mechanism is a two-step process: knock out of one neutron followed by the decay of the He-5 resonance. The shape of the (alpha+n) two-body invariant mass spectrum is interpreted as mainly reflecting the 5He ground state which is a J(pi) = 3/2(-) resonance. However, no evidence for correlations between cu particles and neutrons is observed in the momentum widths of the distributions. It is demonstrated that a combined analysis of the two-body invariant mass spectrum and an appropriate correlation function may be used to determine the properties of the intermediate resonance. (C) 1998 Elsevier Science B.V.
44.	Borge, M. J. G., et al. (author) Probing the Li-11 halo structure through beta-decay into the Be-11() (18 MeV) state 1997 In:* Nuclear Physics A. - 0375-9474. ; 613:3, s. 199-208 Journal article (peer-reviewed)abstract An experimental study of beta-delayed charged particles (H, He, Be) from Li-11 shows a beta-feeding to an excited state at 18.15(15) MeV in Be-11 with a large Gamow-Teller strength, B-GT greater than or equal to 1.6. Branching ratios and reduced widths of 2-, 3- and 5- particle decay channels of this state are extracted, A strong suppression of the neutron branch from the 18 MeV state to the Be-10(g.s.) is observed, We suggest that the measured partial width may be sensitive to the (p(1/2))(2) component in the Li-11 halo, A rough estimate indicates that the (p(1/2))(2) component is not the dominant one in the halo wave-function.
45.	Borge, M. J. G., et al. (author) Scattering of the halo nucleus 11Li and its core 9Li on 208Pb at energies around the Coulomb barrier 2012 In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 381:1, s. Art. no. 012085- Conference paper (peer-reviewed)abstract The first measurement of the elastic scattering of the halo nucleus 11Li and its core 9Li on 208Pb at energies around the Coulomb barrier is presented. The 11Li reaction showed a large cross section for the breakup channel, even at energies well below the barrier. The analysis of the 11Li + 208Pb scattering data in terms of the continuum-discretized coupled-channel calculations indicates that the effect of the coupling to the breakup channels produces a strong suppression of the elastic cross section at energies above and below the barrier. This effect is mainly due to the strong Coulomb coupling to the dipole states in the low-lying continuum of 11Li.
46.	Borge, M. J. G., et al. (author) Scattering of the halo nucleus Li-11 and its core Li-9 on Pb-208 at energies around the Coulomb barrier 2012 In: Journal of Physics: Conference Series. - 1742-6588 .- 1742-6596. ; 381 Conference paper (peer-reviewed)abstract The first measurement of the elastic scattering of the halo nucleus Li-11 and its core Li-9 on Pb-208 at energies around the Coulomb barrier is presented. The Li-11 reaction showed a large cross section for the breakup channel, even at energies well below the barrier. The analysis of the Li-11 + Pb-208 scattering data in terms of the continuum-discretized coupled-channel calculations indicates that the effect of the coupling to the breakup channels produces a strong suppression of the elastic cross section at energies above and below the barrier. This effect is mainly due to the strong Coulomb coupling to the dipole states in the low-lying continuum of Li-11.
47.	Chulkov, L. V., et al. (author) Large spin alignment of the unbound He-5 fragment after fragmentation of 240 MeV/nucleon He-6 1997 In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 79:2, s. 201-204 Journal article (peer-reviewed)abstract Peripheral fragmentation of a 240 MeV/nucleon beam of the halo nucleus He-6 incident on carbon target has been studied in a kinematically complete experiment. It is found that one-neutron stripping to the unbound nucleus He-5 is the dominant fragmentation mechanism and that it leads to a spin alignment of He-5 in a plane perpendicular to the He-5 momentum vector. This is expected to be a common feature for all neutron halo nuclei.
48.	Golubkova, T. A., et al. (author) Transition from direct to sequential two-proton decay in s–d shell nuclei 2016 In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 762, s. 263-270 Journal article (peer-reviewed)abstract The transition between different mechanisms of two-proton decay in exotic nuclei and the governing physical conditions are generally studied. To perform this large-scale survey, the direct-decay model, which is widely used, was improved by generalizing the semi-analytical approaches used before. The improved model provides a flawless phenomenological description of three-body correlations in 2p decays, as is demonstrated by several examples of decays of low-lying states in 16Ne. Different transition mechanisms are shown to occur beyond the proton dripline for s–d shell nuclei. It is found that the transition dynamics of 2p-emitters allows the extraction of the width of the ground-state resonance of the core+p subsystem. The practical application of the method is illustrated by determining properties of the 14F ground state derived from the Ne15?O13+2p decay data, and of the 29Cl ground state derived from the Ar30?S28+2p decay data.
49.	Grigorenko, L. V., et al. (author) Lifetime and Fragment Correlations for the Two-Neutron Decay of O-26 Ground State 2013 In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 111:4 Journal article (peer-reviewed)abstract The structure and decay of O-26 are investigated in a three-body O-24 + n + n model suitable for studies of the long-lived (including radioactivity time scale) states. We have found extremely strong effects of the subbarrier configuration mixing on the decay width of true 2n emitters due to core recoil and neutron-neutron final state interaction. This effect far exceeds the analogous effect in the true 2p emitters. Our calculations provide reasonably narrow boundaries for the lifetime vs decay energy dependence for the true 2n emission. An upper limit of similar to 1 keV for the decay energy of the unbound O-26 is inferred based on the recent experimental lifetime value.
50.	Grigorenko, L. V., et al. (author) Two-neutron radioactivity and four-nucleon emission from exotic nuclei 2011 In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 84:2 Journal article (peer-reviewed)abstract A theoretical method for estimates of a width of "true" four-nucleon decays is developed. Several candidate isotopes to possess this property are considered. Our lifetime estimates compare one-neutron, true two-neutron, and true four-neutron emissions at similar conditions. Prospects of experimental search for two-neutron, four-proton, and four-neutron radioactivity are discussed.

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